binding-problems.rb

# I have a proc that I would like to initialize a variable in scope for before it runs.

[20] pry(#<AnalyzeDocumentJob>)> [callback.class, callback.binding.class]
=> [Proc, Binding]
[21] pry(#<AnalyzeDocumentJob>)> [callback.send(:local_variables).include?(:word_count), 
                                  callback.binding.local_variables.include?(:word_count)]
=> [false, false]
  
# (Failed) attempts to set the variable are below

[11] pry(#<AnalyzeDocumentJob>)> callback.binding.eval("word_count = 0")
=> 0
[21] pry(#<AnalyzeDocumentJob>)> [callback.send(:local_variables).include?(:word_count), 
                                  callback.binding.local_variables.include?(:word_count)]
=> [false, false]
  
[13] pry(#<AnalyzeDocumentJob>)> eval("word_count = 0", callback.binding)
=> 0
[21] pry(#<AnalyzeDocumentJob>)> [callback.send(:local_variables).include?(:word_count), 
                                  callback.binding.local_variables.include?(:word_count)]
=> [false, false]

[3] pry(#<AnalyzeDocumentJob>)> callback.binding.local_variable_set(:word_count, 0)
=> 0
[4] pry(#<AnalyzeDocumentJob>)> callback.binding.local_variable_get(:word_count)
NameError: local variable `word_count' is not defined for #<Binding:0x00007fb918075868>
[12] pry(#<AnalyzeDocumentJob>)> callback.binding.instance_variables
=> []

[3] pry(#<AnalyzeDocumentJob>)> callback.instance_eval do
[3] pry(#<AnalyzeDocumentJob>)*   word_count = 0
[3] pry(#<AnalyzeDocumentJob>)*   call
[3] pry(#<AnalyzeDocumentJob>)* end  
NoMethodError: undefined method `+' for nil:NilClass
from counting_service.rb:9:in `block in <class:CountingService>'
  
[10] pry(#<AnalyzeDocumentJob>)> callback.send(:eval, "word_count = 0")
=> 0
[21] pry(#<AnalyzeDocumentJob>)> [callback.send(:local_variables).include?(:word_count), 
                                  callback.binding.local_variables.include?(:word_count)]
=> [false, false]

[41] pry(#<AnalyzeDocumentJob>)> callback.binding.instance_eval do
[41] pry(#<AnalyzeDocumentJob>)*   word_count = 0
[41] pry(#<AnalyzeDocumentJob>)* end  
=> 0
[42] pry(#<AnalyzeDocumentJob>)> callback.binding.instance_variables
=> []
[43] pry(#<AnalyzeDocumentJob>)> callback.binding.local_variables
=> []
  
[36] pry(#<AnalyzeDocumentJob>)> callback.instance_eval do
[36] pry(#<AnalyzeDocumentJob>)*   word_count = 0
[36] pry(#<AnalyzeDocumentJob>)* end  
=> 0
[44] pry(#<AnalyzeDocumentJob>)> [callback.send(:local_variables).include?(:word_count), 
                                  callback.binding.local_variables.include?(:word_count)]                                    
=> [false, false]